Jim,
Could it be that you transferred chloramphenicol but not the F plasmid
(chloramphenicol on a transposon for example)? Some phages are specific of
strains carrying the F plasmid, this could allow to check rapidly the presence
of the F plasmid.
Cheers
Joel
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Joel L. Vanneste
The Horticulture and Food Research Institute of New Zealand Ltd
Ruakura Research Centre,
Private Bag 3123, Hamilton, e mail: VANNESTEJ%RUASV1 at ruakura.cri.nz
New Zealand fax 64 7 838 5073
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